Centering on a historical review and analysis of adult Christian education in small groups, this study was designed to identify certain conditions surrounding the formation and operation of selected small groups, to discover their distinctive educational features, and to suggest guidelines for effective use of the small group approach. The role of small groups was traced from the ministry of Jesus and the early apostolic church through the catechetical classes (second century to sixth), the decline of learning, and the Middle Ages. Movements from the 1500's through the 1800's were also described, followed by adult Bible classes, the Koinonia movement, participation training, and other developments in twentieth century American Protestantism. These were among the guidelines formulated: (1) small group members should be fairly diverse in talents and skills, but compatible in values and norms; (2) study should alternate with opportunities for practical application; (3) mutual trust and a sense of community and personal identification should be fostered; (4) the group should be fairly permanent, with regular and frequent meetings; (5) members should have a common purpose or cause; (9) ideally, all members should be trained for performance of responsibilities within the group. (LY)